package com.liyy.leetcode.editor.cn;

//题目编号:206
//题目标题:反转链表	
//题目标记:reverse-linked-list	

//题目描述:
//反转一个单链表。 
//
// 示例: 
//
// 输入: 1->2->3->4->5->NULL
//输出: 5->4->3->2->1->NULL 
//
// 进阶: 
//你可以迭代或递归地反转链表。你能否用两种方法解决这道题？ 
// Related Topics 链表
	
public class ReverseLinkedList {
  
    public static void main(String[] args) {
       Solution solution = new ReverseLinkedList().new Solution();
    }
  
//leetcode submit region begin(Prohibit modification and deletion)
/**
 * Definition for singly-linked list.
 * public class ListNode {
 *     int val;
 *     ListNode next;
 *     ListNode(int x) { val = x; }
 * }
 */
class Solution {
    public ListNode reverseList(ListNode head) {
        ListNode prev = null;
        ListNode curr = head;
        while (curr != null) {
            //提前存储好下一个要遍历的元素
            ListNode next = curr.next;

            curr.next = prev;
            prev = curr;
            curr = next;
        }
        return prev;
    }
}
//leetcode submit region end(Prohibit modification and deletion)

}